Is There an Open Standard for Network Maps?

mattski asks: "I am currently working on a project that generates network maps within a GUI, running on Solaris, which then needs to be exported somehow. What would you want to see as an export format for network maps and why? Take into account that the user must be able to manipulate the 'map' after it has been exported. I guess some options include XML or maybe even VRML but have you got any other thoughts?"